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Abstract Hybrid polyaromatic hydrocarbons (PAHs) consisting of helicene and acene domains, referred to as [7]heli‐D‐acenes, are introduced as scaffolds to generate enantiopure twisted acenes (heli‐twistacenes) by a torque, lock, and propagate (TLP) approach. Computational methods with and without dispersion corrections were used to explore the structural and electronic features of these PAHs and to explore the possible formation of twistomers that might complicate reaction mixtures. Syntheses of unsubstituted and disubstituted members of the [7]heli‐D‐acene series confirmed the viability of the TLP approach, and together with the computational results, provided proof‐of‐concept of this new approach as a viable means to generate enantiopure twisted‐acenes. The X‐ray structures, absorption, fluorescence, phosphorescence, and CD spectra of these first generation heli‐acenes are compared to the structure and photophysical properties of pentacene and [7]helicene. A high barrier for the enantio‐enriched M enantiomer of 19,24‐dicyano[7]heli‐D‐anthracene verified its configurational stability at room temperature. 

Abstract Efficient heterogeneous photosensitizing materials require both large accessible surface areas and excitons of suitable energies and with well‐defined spin structures. Confinement of the tetracationic cyclophane (ExBox⁴⁺) within a nonporous anionic polystyrene sulfonate (PSS) matrix leads to a surface area increase of up to 225 m²g⁻¹in ExBox•PSS. Efficient intersystem crossing is achieved by combining the spin‐orbit coupling associated to Br heavy atoms in 1,3,5,8‐tetrabromopyrene (TBP), and the photoinduced electron transfer in a TBP⊂ExBox⁴⁺supramolecular dyad. The TBP⊂ExBox⁴⁺complex displays a charge transfer band at 450 nm and an exciplex emission at 520 nm, indicating the formation of new mixed‐electronic states. The lowest triplet state (T₁, 1.89 eV) is localized on the TBP and is close in energy with the charge separated state (CT, 2.14 eV). The homogeneous and heterogeneous photocatalytic activities of the TBP⊂ExBox⁴⁺, for the elimination of a sulfur mustard simulant, has proved to be significantly more efficient than TBP and ExBox⁺⁴, confirming the importance of the newly formed excited‐state manifold in TBP⊂ExBox⁴⁺for the population of the low‐lying T₁state. The high stability, facile preparation, and high performance of the TBP⊂ExBox•PSS nanocomposites augur well for the future development of new supramolecular heterogeneous photosensitizers using host–guest chemistry.